This study is designed to define phenotypic traits in multigenerational Utah families, to create a repository of phenotype/genotype information, and to identify genes and genetic loci that determine common human traits and susceptibility to human disease. Fifteen families have been selected for the pilot phase of this project. Questionnaires have been developed, and families spend a full day (a Saturday) at the GCRC undergoing various blood and physical tests. Each family member visits a total of 20 testing stations. The first fifteen families have completed both the study questionnaire phase of the project and the physical and laboratory testing. In addition to the preliminary data collected on three-generation Utah reference families, DNA samples have been collected from families and individuals with common diseases, and have been processed in the GCRC DNA Extraction Core. These studies have resulted in the identification of two epilepsy genes, a gene responsible for inherited benign neonatal seizures, and a retinal transporter gene present in a portion of common, age-related macular degeneration.